1. Technical Field
The invention relates to tape stapling tools used in agriculture, among other applications. Tools of this kind have a reel of tape which is made to encircle or wrap around a group of branches, twigs, etc. so that once they are encircled, the tape is stapled together around the group or bunch of branches or twigs, which are thus fastened together.
2. Prior Art
In a known tool of this type, there is a tape stapler manufactured in Japan and commercialized under the brand name MAX TAPENER, which has been on the market for more than twenty years. It is made up of a lower body which houses a reel of tape and on which is mounted a stapling device. See Patent CH-A-535101.
The tape that comes from the reel runs towards the front part of the tool where the staple holder device also appears, with a blade or knife to cut the tape once that the loop has been made around the group or bunch also being situated in this front part.
Over the said lower body is arranged an arm which pivots on it and which is operated by a lever, with this arm usually being curved or arc-shaped. The free end of this arm includes a mechanism which, on the arm pivoting towards the front part of the lower body, takes up the end of the protruding tape and pulls on it, then opening again to provide a stretch of tape that closes or covers the gap between the arm and the lower body.
With the arm open, the items to be taped together are housed inside the arc-shaped arm, than forming a loop of tape in the space between the arm and the lower body. Having reached this position, the lever is operated, thus closing the arm and causing the end of the tape being held by the arm to approach the portion coming from the reel through the lower body. Next, the arm mechanism releases the tape, staples together the two ends of the tape and cuts its two-ends, leaving them joined together to form a loop.
The mechanism at the end of the arc-shaped arm is known in itself and from its most outer part towards its interior it has four projections protruding downwards. The most exterior of these has a vertical movement on coming up against a forward projection on the lower body. In the movements of the arm, on being operated by means of the lever, this projection withdraws towards the interior of the mechanism and alters the position of a second projection that moves forwards and backwards. On the first movement, the second projection, being in the forward position, is made to move backwards, and on the second movement, with the projection being in the backward position, is made to move forwards.
Apart from these two projections, the arm mechanism is provided with a third fixed projection, on which the second projection impinges on its backwards movement. This third projection is provided with a transverse hole, in which the point that stands out from the lower end of the second projection is received, so as to take up the tape coming from the lower body.
The most inner projection is fixed and has a horizontal base, in which there are two recesses to receive the points of the staples which are to be found in the staple holder or loader housed in the lower body.
The end of the tape coming from the lower body juts upwards in the proximity of the front end of the said lower body, just behind the stop that the forward projection of the mechanism in the arc-shaped arm comes up against and inside a forward section of the staple loader that protrudes from the lower body. This end of the tape is taken up between the second projection in the arm mechanism and the third fixed projection and is released after the second projection moves forward when the arm is operated again.
From the front end of the lower body a blade or knife protrudes upwards, with this blade emerging from inside the forward section of the staple loader and towards the projections from the mechanism in the arc-shaped arm, more specifically between the third and fourth fixed projections.
The fourth projection of the mechanism in the arc-shaped arm remains substantially above the outlet for the staples coming from the staple loader in the position of the arm closed over the lower body.
The staple loader, holder or feeder is assembled inside the upper section of the lower body and is of the conventional type commonly used for stapling. The loader is mounted on a spring situated in the interior of the lower body, in such a way that in the normal position its front end is raised.
The front end of the staple loader finishes in a stop that makes contact with the most forward staple, and a vertical part protrudes from the bottom of lower body and is directed upwards just below the base of the first staple, each staple being "U"-shaped with the opening upwards.
In the descending movement of the arc-shaped arm, the end of the staple loader is forced downwards, thus overcoming the action of the spring, with which the cutting blade protrudes upwards and cuts the tape. At the same time, the vertical part mentioned in the previous paragraph forces the first staple against the fourth projection, by way of an anvil, of the mechanism of the arc-shaped arm, with which the staple is closed.
These tape stapling tools which are already known have several disadvantages, among .which the following can be pointed out:
The container for the reel of tape is situated in the lower body, more specifically in a lower casing which is usually made of plastic material. This container has a laterally articulated cover and its base has a central boss which houses in a hole cut in the cover. From this container, the tape runs along an elongated cavity made in the lower body itself, with the tape running along this until its front end travels freely. This elongated cavity has a hinged cover. PA1 A container in the lower body with a free intake for the reel of tape, in which the reel of tape rests freely, thus improving its freedom of movement and making the tape feeding movement easier. PA1 A cover that covers the intake or access for the reel of tape and at the same time acts as an adjustable controller for the tension of the tape. PA1 A perfect guideway for the tape. PA1 A lower body which includes the container for the reel of tape, together with the guideway for the tape, the cover for the intake or access for the reel of tape, as well as the means necessary for connection to the lower base. PA1 A lower base which is pressure fitted onto the lower body. PA1 A mechanism that takes up the tape positioned at the end of the pivoting arm. PA1 A staple loader or feeder slide which makes it easier to load the staples and also provides a pusher which cannot be extracted from the loader, with which its possible loss is prevented. PA1 A lever and arc-shaped arm assembly which enables the opening of the arc-shaped arm to be regulated at will and in accordance with the needs of application.
The arrangement of the hinged or articulated covers on the body for the reel of tape and for leading the tape cause frequent breakage of the lower body, as the material becomes weakened in the hinged area due to use.
These known tools usually have a metal strip fastened to the interior of the cavity along which the tape runs and close to its outlet, for the purpose of controlling the outlet of the tape by exerting a certain pressure on it.
The positioning of this metal strip is particularly problematic, given that it is an independent part of the lower body which needs to be situated and fixed in the interior of the said lower body.
On the other hand, the connection between the lower plastic body and the metallic lower base is carried out by means of rivets, which makes the assembly of the two parts more complicated and expensive.
The opening provided by the arc-shaped arm to enable entry of the items to be taped together is always the same, meaning that its use in real cases is limited on not being able to receive certain sizes of the said items.
The staple loader used by the known tape staplers receive the staples from the rear part of the tool, so that it is necessary to totally extract the pusher for the staples through the said rear part, which is an inconvenience because of the difficulty of housing the staples and because of the possibility of the pusher getting lost.
The mechanism at the end of the arc-shaped arm is made up of three basic interlaced parts housed in plastic supports which are inserted in the said ends. Of these three basic parts, two are the forward projection or pusher and the second projection or claw, and the third is another part that acts between the previous two and is provided with a hole or window and a spout with which the action of the mechanism is carried out. In the same way, the plastic supports that hold the mechanism are in their turn connected with another fixing pin for both, which carries out its function in the movements of the pusher and the claw.
This conventional mechanism that raises and lowers the pusher and which makes the claw swing either towards the third projection or bracket or else outwards, has an excessive number of parts, which, although they ensure correct operation, make the whole assembly more expensive.